Posted
by
samzenpus
on Thursday February 03, 2011 @12:41AM
from the dust-it-all dept.

cylonlover writes "Refining an existing technique that's been used to successfully recover fingerprint detail from smooth objects such as glass and plastic, forensic scientists have managed to create a kind of photo negative of fingerprint impressions on fabric. It's a bit hit and miss at the moment, but even when clear ridge detail isn't retrieved, the technique could still prove useful to investigators looking for other evidence."

I remember seeing something on similar FBI files, which IIRC was over 5 years ago. They had bloodied palm and fingerprints left on a sheet. The problem wasn't so much a lack of evidence but that the pattern of the material intefered with the prints to an extent where a jury couldn't be expected to be able to identify it as a match. They used image processing to essentially subtract the patterning from an unstained area of the material to end up with a relatively clean image.

As well as being subjective there is also the issue of partial or distorted prints. It is rare to get a perfect print like they do on CSI.

DNA matching is also not all it's cracked up to be either. Again there are issues with poor samples and the practice of "amplifying" to obtain a usable amount of material. Even with a good sample matching is not 1:1, you only get a probability. At best most real world tests are only accurate to about 1 in 10,000 at best, pretty crappy odds.

I don't actually have an opinion on all this at all - i'm in another country and didn't really follow the case of a practitioner of a brand of football i have no interest in. it's just all that was on the news for a good while anywhere in the world. i put it down to a slow news year.

There's probably not a lot on the net due to how long abo it was but here's one thing in L-space:

P. D. Drummond, Green Light on the Rainbow Warrior. Auckland Applied Research Office Information Bulletin, (1987). [ Article on the use of lasers for forensic work, which successfully identified the terrorists who sank the Rainbow Warrior - a civilian vessel in Auckland Harbour.]

The success rate for recovery is still quite low, with only around 20 percent of the public said to consistently leave good ridge detail or indicate target areas for DNA collection due to the presence of sweat.

"Refining an existing technique that's been used to successfully recover fingerprint detail from smooth objects such as glass and plastic, forensic scientists have managed to create a kind of photo negative of fingerprint impressions on fabric. It's a bit hit and miss at the moment, but even when clear ridge detail isn't retrieved, the technique could still prove useful to investigators looking for other evidence."